Four-dimensional is also known as four-dimensional ultrasound, four-dimensional ultrasound does not need to bring a lot of information, to bring a good appointment to check the ticket, some food can be. Four-dimensional ultrasound is usually 22 to 28 weeks pregnant to check, usually regular good pregnancy maternity examination, usually in four-dimensional ultrasound before the doctor will write a good prescription, so that the patient to pay the fee to make an appointment, the day of the examination to bring a good appointment to check the bills, can prove that has been paid for, and have to check the vouchers of the four-dimensional ultrasound can be, do not need to bring a lot of other information. Four-dimensional ultrasound before the examination to eat properly, you can also bring some cookies, bread, cakes and other food, some babies do four-dimensional ultrasound do not cooperate with the examination, appropriate food to increase the sugar in the blood, may allow the fetus to move, convenient to one-time through the examination. It is recommended that every mother should go to the hospital to do four-dimensional ultrasound examination, through the dynamic image to understand the fetal face, limbs, internal organs and so on whether there are deformities, there are abnormalities and then further examination and targeted treatment. It is recommended to go to a regular hospital for 4D ultrasound examination, operated by professionals to improve the accuracy.